Pertussis toxin inhibits the colony-stimulating activity of Eotaxin. (A) Pertussis toxin in the range of 1 to 100 ng/mL blocked the colony-stimulating activity of Eotaxin (100 ng/mL). The number of cells per plate collected from the GM-CFU assay is shown in (B). Three different experiments were performed. The results shown are of one representative experiment. Each point is the mean of three determinations ± SD.